Inhibiting an enzyme involved in DNA repair shows promise as a strategy
for preventing and treating some forms of breast cancers, according to two
new studies by researchers from England and Sweden (Bryant et al. Nature. 2005;434:913-917 and Farmer et al. Nature. 2005;434:917-921).

Up to 5% to 10% of breast cancer in women is attributable to mutations
in BRCA1 and BRCA2. These
genes encode enzymes that are involved in repairing damaged DNA. In breast
tissue, mutations in these genes cause the cells to become cancerous.